Preparation and packaging method of intelligent temperature control thermal management phase change material

Abstract

The invention relates to the technical field of safety materials, in particular to a preparation and packaging method of an intelligent temperature control thermal management phase change material, when the phase change material is prepared, the heat conduction and heat dissipation performance of the material is enhanced by adding carbon nanotubes, rapid heat dissipation is achieved, and the energy conversion efficiency is enhanced; metal foils such as copper foils are removed, so that the heat absorption capacity of the phase change material structure is enhanced while the material cost is reduced; and the packaging adopts a process of firstly cutting and then assembling, so that the phase-change material is packaged more quickly, the equipment investment is lower, and the heat-insulating substrate material can adsorb more phase-change materials to improve the performance.

Description

Technical Field

[0001] The present application relates to the technical field of safety materials, and in particular to a method for preparing and packaging an intelligent temperature-controlled thermal management phase change material. Background Art

[0002] With the development of new energy vehicles, both winter and summer, over-cold and over-heated temperatures have a significant impact on batteries. Therefore, creating an excellent working environment is an important factor for batteries to maximize their advantages, regardless of the cold or hot seasons. At present, there is a lack of effective control measures for thermal runaway and thermal management of batteries. Battery thermal runaway is caused by multiple uncontrollable reasons. Once thermal runaway occurs, it will cause immeasurable safety accidents, and current firefighting measures cannot effectively extinguish the fire: in extremely cold conditions, the battery power cannot be efficiently used, which is the biggest disadvantage in the cold season.

[0003] Existing thermal insulation materials are generally metal foil and aerogel structures, which use low thermal conductivity to prevent heat from being transmitted, but are prone to heat accumulation. At the same time, the thermal insulation performance of aerogel mainly depends on its internal nanoporous structure. In practical applications, this structure may be affected by many factors, such as temperature, pressure, humidity, etc., which will cause deviations in the direction of the thermal insulation effect. When the heat source experiences thermal runaway and the temperature is too high, the aerogel structure will collapse and melt, resulting in failure of the thermal insulation performance. In addition, aerogel particles cannot be formed independently and need to be combined with other fiber materials. After combination, the adhesion is poor and it is easy to fall off. Therefore, other organic materials are needed for packaging. The packaging process is relatively complicated and the cost is high.

[0004] The intelligent temperature regulation thermal management phase change material is an advanced composite material that can absorb or release a large amount of latent heat during the phase change process to achieve energy storage and release; when the ambient temperature exceeds its phase change point, the material will absorb and store heat to lower the ambient temperature; on the contrary, when the ambient temperature is lower than the phase change point, the material will release the previously stored heat to increase the ambient temperature. Under extremely low temperature conditions, the material can also generate heat under low voltage to ensure that the ambient temperature is maintained at a constant level, thereby maintaining the excellent performance of the product and effectively controlling the temperature of the surrounding environment. Summary of the invention

[0005] The present application provides a method for preparing and packaging an intelligent temperature-controlled thermal management phase change material, which can enhance the thermal conductivity and heat dissipation performance of the phase change material and improve the energy conversion efficiency.

[0006] In order to achieve the above-mentioned purpose, the present application provides a preparation and packaging method of an intelligent temperature control thermal management phase change material, comprising the following steps: Step 1: Prepare an insulating base material; Step 2: Cut and bake the insulating base material, the baking temperature is 30-120°C, and the baking time is 0.5h-2h; Step 3: Prepare a composite phase change solution using phase change material, carbon nanotubes, a composite auxiliary solution, a pH regulator, a moisturizer, a thickener, and a structural auxiliary; Step 4: Soak the baked insulating base material in the composite phase change solution; Step 5: After the insulating base material and the composite phase change solution are completely infiltrated and composited, they are cured to obtain a composite phase change structure, the curing temperature is 30-50°C, the curing time is 0.2-0.5h, and the packaging material is sealed; Step 6: Prepare a heating material, and seal it with a packaging material; Step 7: Prepare a packaging structure using the packaging material; Step 8: Place the sealed composite phase change structure and the heating material together into the packaging structure, evacuate, and perform hot pressing.

[0007] Furthermore, in step 1, the thermal insulation base material is one or more of polyester fiber felt, polyimide felt, polyurethane felt, polypropylene felt, pre-oxidized silk felt, aerogel felt, ceramic wool felt, glass fiber felt, rock wool and glass wool felt.

[0008] Furthermore, in step 3, the configuration of the composite phase change solution using phase change material, carbon nanotubes, composite auxiliary solution, pH regulator, humectant, thickener and structural additive includes the following steps: step 3.1: mixing the composite auxiliary and the solvent in a ratio of 1:0.5-2 to obtain a composite auxiliary solution; step 3.2: mixing the phase change material, composite auxiliary solution, carbon nanotubes, humectant, thickener, structural additive and pH regulator in a ratio of 1:1-2:0.1-0.5:0.1-0.3:0.1-0.3:0.1-0.3:0.3-0.8; step 3.3: mixing evenly using a stirring device, the rotation speed of the stirring device is 600-1500r / min, and the mixing temperature is 30-60°C.

[0009] Furthermore, in step 3, the phase change material is one or more of crystalline hydrated salts, paraffin, fatty acids and polyols; the composite auxiliary agent is one or more of silicates, silicon oxides and silicon hydroxides; and the solvent is one or more of cyclohexane, cyclohexanone, water, dilute acid and dilute alkali.

[0010] Furthermore, in step 3, the humectant is one or more of glycerol, polyethylene glycol and sodium tripolyphosphate; the thickener is one or more of modified starch, gelatin, sodium carboxymethyl cellulose and cellulose; the structural additive is one or more of floating beads, glass microbeads and hollow ceramic microbeads; the pH adjuster is one or more of hydrochloric acid, sulfuric acid, acetic acid, sodium hydroxide, sodium carbonate, ammonia water and ethanolamine.

[0011] Furthermore, in step 3, the carbon nanotubes are one or more of single-walled carbon nanotubes and multi-walled carbon nanotubes.

[0012] Furthermore, in step 4, the immersion method is vacuum immersion or roller immersion.

[0013] Furthermore, in steps 5-7, the packaging material is one or more of polyester, aluminum foil, polyethylene, nylon and cast polypropylene.

[0014] Furthermore, in step 6, the heating material includes a conductor, carbon nanotubes and a polymer, wherein: the conductor is a metal conductor; the carbon nanotubes are one or more of single-walled carbon nanotubes and multi-walled carbon nanotubes; the polymer is one or more of polypropylene, polyethylene and polyethylene terephthalate; during preparation, the carbon nanotubes are dispersed in a polymer solution, coated on the conductor as a whole, and sealed with a packaging material.

[0015] Furthermore, in step 7, the size of the packaging structure is larger than that of the composite phase change structure; the vacuum degree during vacuuming is maintained at 0.01-0.1 MPa, and the hot pressing molding adopts three-sided preheating and pressing at a temperature of 120-220°C.

[0016] The present application provides a method for preparing and packaging an intelligent temperature control thermal management phase change material, which has the following beneficial effects:

[0017] When preparing phase change materials, the present application enhances the thermal conductivity and heat dissipation performance of the materials by adding carbon nanotubes, thereby achieving rapid heat dissipation and enhancing energy conversion efficiency; removing metal foils such as copper foil, thereby reducing material costs and enhancing the heat absorption capacity of the phase change material structure; and packaging adopts a cutting-before-assembly process, which makes the packaging of phase change materials faster, reduces equipment investment, and is more conducive to the insulation base material to absorb more phase change materials to achieve performance improvement. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting a part of this application are used to provide a further understanding of this application, so that other features, purposes and advantages of this application become more obvious. The schematic embodiment drawings and their descriptions of this application are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0019] Figure 1 This is a picture of the finished product obtained after packaging according to the embodiment of the present application;

[0020] Figure 2 It is a schematic diagram of the composition of the intelligent temperature control thermal management phase change material provided according to the embodiment of the present application;

[0021] Figure 3 This is a state diagram of the finished product obtained after packaging according to the embodiment of the present application when the heat source is 1500°C;

[0022] In the figure: 1-heating material, 2-thermal insulation base material, 3-composite phase change structure, 4-packaging material. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0024] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0025] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0026] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0027] In addition, the term "plurality" shall mean two or more.

[0028] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0029] like Figure 2 As shown, the present application provides a method for preparing and packaging an intelligent temperature control thermal management phase change material, which enhances the thermal conductivity and heat dissipation performance of the product by adding carbon nanotubes, and utilizes the tunnel effect and large π bond structure of carbon nanotubes to achieve rapid heat dissipation and enhance energy conversion efficiency, specifically comprising the following steps:

[0030] Step 1: preparing a heat-insulating base material 2; the heat-insulating base material 2 is one or more of polyester fiber felt, polyimide felt, polyurethane felt, polypropylene felt, pre-oxidized silk felt, aerogel felt, ceramic wool felt, glass fiber felt, rock wool and glass wool felt;

[0031] Step 2: cutting and baking the heat-insulating base material 2 at a temperature of 30-120° C. for a time of 0.5 h to 2 h;

[0032] Step 3: preparing a composite phase change solution using phase change materials, carbon nanotubes, composite auxiliary solution, pH regulator, moisturizer, thickener and structural auxiliary agent;

[0033] Step 3.1: Mix the composite auxiliary agent and the solvent in a ratio of 1:0.5-2 to obtain a composite auxiliary agent solution;

[0034] Step 3.2: Mix the phase change material, the composite additive solution, the carbon nanotubes, the humectant, the thickener, the structural additive and the pH adjuster in a ratio of 1:1-2:0.1-0.5:0.1-0.3:0.1-0.3:0.1-0.3:0.3-0.8;

[0035] Step 3.3: Mix evenly using a stirring device, the speed of the stirring device is 600-1500r / min, and the mixing temperature is 30-60°C;

[0036] The phase change material is one or more of crystalline hydrated salts, paraffin, fatty acids and polyols; the composite additive is one or more of silicates, silicon oxides and silicon hydroxides; the solvent is one or more of cyclohexane, cyclohexanone, water, dilute acid and dilute alkali; the humectant is one or more of glycerol, polyethylene glycol and sodium tripolyphosphate; the thickener is one or more of modified starch, gelatin, sodium carboxymethyl cellulose and cellulose; the structural additive is one or more of floating beads, glass microbeads and hollow ceramic microbeads; the pH adjuster is one or more of hydrochloric acid, sulfuric acid, acetic acid, sodium hydroxide, sodium carbonate, ammonia water and ethanolamine; the carbon nanotube is one or more of single-walled carbon nanotubes and multi-walled carbon nanotubes;

[0037] Step 4: soaking the baked heat-insulating base material 2 in the composite phase change solution; the soaking method is vacuum soaking or roller soaking;

[0038] Step 5: After the heat-insulating base material 2 and the composite phase change solution are completely infiltrated and compounded, they are cured to obtain a composite phase change structure 3. The curing temperature is 30-50° C., the curing time is 0.2-0.5 h, and the composite phase change structure 3 is sealed by a packaging material 4.

[0039] Step 6: Prepare the heating material 1 and seal it with the packaging material 4;

[0040] The heating material 1 includes a conductor, a carbon nanotube and a polymer, wherein: the conductor is a metal conductor, preferably one or more of gold, silver, copper and aluminum; the carbon nanotube is one or more of a single-walled carbon nanotube and a multi-walled carbon nanotube; the polymer is one or more of polypropylene, polyethylene and polyethylene terephthalate;

[0041] During preparation, the carbon nanotubes are dispersed in a polymer solution, coated on a conductor as a whole, and sealed with a packaging material 4;

[0042] The energy requirement for heating material 1 is electric heating, the voltage range is preferably 5-50V, and the temperature reached after heating is preferably 20-50°C.

[0043] Step 7: Prepare a packaging structure using packaging material 4; packaging material 4 is one or more of polyester, aluminum foil, polyethylene, nylon and cast polypropylene; the packaging structure is preferably in the shape of a packaging bag;

[0044] Step 8: Place the sealed composite phase change structure 3 and the heating material 1 into the packaging structure, evacuate, and perform hot pressing; the size of the packaging structure is larger than that of the composite phase change structure 3; the vacuum degree during evacuation is maintained at 0.01-0.1 MPa; hot pressing adopts three-sided preheating and pressing at a temperature of 120-220°C.

[0045] Furthermore, the method of the embodiment of the present application is generally used to heat-press the composite phase change structure 3, the heating material 1 and the packaging structure as a whole to form a plate-like structure, such as Figure 1 As shown, it is used as an insulation board or insulation pad and is arranged in a thermal insulation device. The material as a whole has the functions of low-temperature heat conduction, medium-temperature heat absorption and high-temperature heat insulation.

[0046] Specifically, in actual application, when in an extremely cold environment, the heating material 1 can be heated by an external power supply, thereby increasing the overall temperature of the environment; when the isolated heat source has an abnormal temperature, before reaching the low temperature of the phase change boundary temperature, the composite phase change structure 3 of the insulation board will conduct heat to assist the abnormal heat source in dissipating heat and prevent the temperature of the abnormal heat source from gradually rising to the self-heating stage; when the abnormal heat source is thermally runaway and the temperature reaches the phase change point of the composite phase change structure 3 of the insulation board, the composite phase change structure 3 begins to undergo a phase change, undergoing a solid-gas conversion, and will rapidly absorb heat, insulate, disperse, and discharge heat. The heat is slowly released through the carbon nanotube tunnel with the gas to maintain the temperature balance of the system, and the rest continues to play an auxiliary role in heat conduction to block the spread of heat; when the insulation board absorbs heat to a critical value and the temperature continues to rise, the composite phase change structure 3 continues to phase change and absorbs heat, and then gradually undergoes a process catalytic conversion to generate a network structure crystal. Under continuous high temperature, the residual material is further converted into a porous structure crystal structure, which continues to play an insulating role to prevent the spread of fire.

[0047] More specifically, the flame retardant temperature of the composite phase change structure 3 of the embodiment of the present application is greater than 1200°C. Figure 2 As shown, under high temperature conditions of 1500°C, it is possible to achieve a phenomenon of no heat penetration for more than 1 hour. Even after the composite phase change structure 3 fails, it will not burn and will not produce harmful gases. Compared with the traditional aerogel structure, it will not reduce the impact of thermal runaway by sacrificing heat dissipation. Compared with conventional phase change materials, the present application adds a certain amount of carbon nanotubes during the configuration of the phase change solution to enhance the heat absorption and heat conduction capacity of the phase change material, so that the ambient temperature is always in a relatively low stable state. At a relatively low temperature, it can absorb and store heat with a relatively high thermal conductivity and heat capacity to prevent the temperature of the heat source from further increasing. At high temperatures, a large amount of heat is absorbed through the phase change of the phase change material to prevent heat transfer when thermal runaway occurs. Even after the phase change material fails to absorb heat, the porous inorganic structure left still plays a role in preventing heat transfer. In addition, the present application directly performs vacuum packaging on the cured composite phase change structure 3 and the heating material 1, and then directly performs hot pressing molding, so the packaging process is simple, the cost is reduced, and the packaging efficiency is higher.

[0048] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing and packaging an intelligent temperature control thermal management phase change material, characterized in that: The steps include: Step 1: preparing a thermal insulation base material; Step 2: Cut and bake the thermal insulation base material at a temperature of 30-120°C for a time of 0.5h-2h; Step 3: preparing a composite phase change solution using phase change materials, carbon nanotubes, composite auxiliary solution, pH regulator, moisturizer, thickener and structural auxiliary agent; Step 4: Soaking the baked thermal insulation base material in the composite phase change solution; Step 5: After the thermal insulation base material and the composite phase change solution are completely infiltrated and compounded, they are cured to obtain a composite phase change structure. The curing temperature is 30-50° C., the curing time is 0.2-0.5 h, and the packaging material is used to seal. Step 6: Prepare the heating material and seal it with the packaging material; Step 7: Prepare a packaging structure using packaging materials; Step 8: Place the sealed composite phase change structure and the heating material into the packaging structure, evacuate the structure, and perform hot pressing.

2. The method for preparing and packaging the intelligent temperature control thermal management phase change material according to claim 1, characterized in that: In step 1, the thermal insulation base material is one or more of polyester fiber felt, polyimide felt, polyurethane felt, polypropylene felt, pre-oxidized silk felt, aerogel felt, ceramic wool felt, glass fiber felt, rock wool and glass wool felt.

3. The method for preparing and packaging the intelligent temperature control thermal management phase change material according to claim 2, characterized in that: In step 3, the preparation of a composite phase change solution using phase change material, carbon nanotubes, composite auxiliary agent solution, pH regulator, moisturizer, thickener and structural auxiliary agent includes the following steps: Step 3.1: Mix the composite auxiliary agent and the solvent in a ratio of 1:0.5-2 to obtain a composite auxiliary agent solution; Step 3.2: Mix the phase change material, the composite additive solution, the carbon nanotubes, the humectant, the thickener, the structural additive and the pH adjuster in a ratio of 1:1-2:0.1-0.5:0.1-0.3:0.1-0.3:0.1-0.3:0.3-0.8; Step 3.3: Use a stirring device to mix evenly, the speed of the stirring device is 600-1500r / min, and the mixing temperature is 30-60°C.

4. The method for preparing and packaging the intelligent temperature control thermal management phase change material according to claim 3, characterized in that: In step 3, the phase change material is one or more of crystalline hydrated salts, paraffin, fatty acids and polyols; the composite auxiliary agent is one or more of silicates, silicon oxides and silicon hydroxides; the solvent is one or more of cyclohexane, cyclohexanone, water, dilute acid and dilute alkali.

5. The method for preparing and packaging the intelligent temperature control thermal management phase change material according to claim 3, characterized in that: In step 3, the humectant is one or more of glycerol, polyethylene glycol and sodium tripolyphosphate; the thickener is one or more of modified starch, gelatin, sodium carboxymethyl cellulose and cellulose; the structural additive is one or more of floating beads, glass microbeads and hollow ceramic microbeads; the pH adjuster is one or more of hydrochloric acid, sulfuric acid, acetic acid, sodium hydroxide, sodium carbonate, ammonia water and ethanolamine.

6. The method for preparing and packaging the intelligent temperature control thermal management phase change material according to claim 3, characterized in that: In step 3, the carbon nanotubes are one or more of single-walled carbon nanotubes and multi-walled carbon nanotubes.

7. The method for preparing and packaging the intelligent temperature control thermal management phase change material according to claim 1, characterized in that: In step 4, the soaking method is vacuum soaking or roller soaking.

8. The method for preparing and packaging the intelligent temperature control thermal management phase change material according to claim 1, characterized in that: In steps 5-7, the packaging material is one or more of polyester, aluminum foil, polyethylene, nylon and cast polypropylene.

9. The method for preparing and packaging the intelligent temperature control thermal management phase change material according to claim 1, characterized in that: In step 6, the heating material includes a conductor, a carbon nanotube and a polymer, wherein: The electrical conductor is a metallic conductor; The carbon nanotubes are one or more of single-walled carbon nanotubes and multi-walled carbon nanotubes; The polymer is one or more of polypropylene, polyethylene and polyethylene terephthalate; During preparation, the carbon nanotubes are dispersed in a polymer solution, coated on a conductor as a whole, and sealed with a packaging material.

10. The method for preparing and packaging the intelligent temperature control thermal management phase change material according to claim 1, characterized in that: In step 7, the size of the packaging structure is larger than that of the composite phase change structure; the vacuum degree during vacuuming is maintained at 0.01-0.1 MPa, and the hot pressing molding adopts three-sided preheating and the temperature is 120-220°C.

Images